Improvement in springs



was hf fi WIM- E. U. BENEDICT, OF CHICAGO, ILLINOIS. Letters Patent No. 88,117, dated Mwrch 23, 1869.

IMPROVEMENT IN SPRINGS.

m The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

Be it known that I, E. U. BENEDICT, of Chicago, in the county ofOook, and State ofIllinois, have invented a new and improved Spring; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specification, in which Figure 1 is a view of the improved spring, before pressure is applied upon it.

Figure is a similar view of the same parts, when the spring is exposed to the greatest pressure that it will bear.

Figure 3 is a vertical transverse section, taken centrally through the spring and its bearings and guides. Similar letters of reference indicate corresponding parts in the several figures.

In the construction ofelliptic and semi-elliptic springs, the method hitherto adopted was to unite all the plates, or leaves, composing each bow of the springs, by means ofbands, bolts, orstuds, in such manner that the leaves were so restrained that they would not afford that degree of elasticity, throughout their length, which is affordcd by each spring separately when not so restrained. And when one of the leaves of such spring breaks, as is frequently the case, it is a very laborious operation to substitute a new one in its place.

The nature of my invention consists in the two or more leaves, placed one upon the other, and arranged between a follower, or spring-bar,which is furnished with a compensating bearing-plate, and with side-supports, or guides, and a sill, or bolster, furnished with horizontal end-supports, or guides, whereby each of the leaves of a compound elliptic spring is free to move, independent of its fellow, and whereby, also, the stiffness of the spring .is increased in proportion as the weight of the load is increased, or nice ccrsa, as the weight is decreased.

To enable others skilled in the art to understand my invention, I will describe its construction and operation.

In the accompanying drawings, I have represented a compound semi-elliptic spring, composed of three leaves, I) b I), which may be of an equal width, length, and thickness, or which may beof different lengths, the shortest leaves being arranged upon the longest, so that each leaf will have a proper bearing.

For the purpose of illustrating clearly my improvements, I have represented a spring in fig. 1, before it is compressed, and, in fig. 2, I have shown a spring fully compressed.

A represents a bolster, or cross-head, whose. ends are tenoned, and fitted into grooves, formed in pieces 0 G, which lat-ter are secured perpendicularly to a piece, B, that is parallel to the bolster A.

Between the bolsters-X and piece B, the spring is confined in place by means of end-shoes, 5/9, and sidepieces, 9, and the intermediate side-plates D, which latthe length of the leaves ter are bolted on opposite sides of the bolster A, at the middle of its length,- so as to prevent the spring from lateral displacement at such point.

The bolsterA is allowed to approach or recede from the piece B, and, by means of its tenons, and the shoulders left by the formation thereof, the pieces 0 G will keep this bolster parallel to the said piece B.

The spring consists of narrow strips of steel, b,which are laid one upon the other, between the side-plates g 9, after being properly bent and curved; and upon this spring is placed the bolster A, as clearly shown in the drawings.

By removing the plates. D g g from one side of the frame, within which the spring is applied, any one or more of the leaves I) can be readily removed, and anothersubstituted in its stead.

The ends of the spring bear upon the angular shoes 9 g, which are secured at the angles formed by the pieces B and O C, and these angle-pieces g 9 should be adjusted at such distance apart, with reference to of the spring, and the degree of extension thereof, that the ends of the leaves will have freedom to extend or contract. H The crown of the spring impinges against the bottom edge of the bolster, at the middle of its length, as shown in fig. l, and at and near this point a plate, a, is aflixedto the'bolster, which plate is curved, so as to present an arc whose radius is equal to that of the spring when fully compressed, as shown in fig. 2.

It will be seen, from the above description, that I employ, in the construction of my spring, two or more plates, of equal or nearly equal length, bent and tempered in any suitable manner, and held in place between side-plates, 0r jaws D D and g g, and that I do not clamp or rivet the leaves together, as heretofore practised, but allow each leaf freedom to operate as a spring its entire length.

It will also be seen that I form a curved bearing for the crown of the spring, which bearing will extend over a greater length of the ter is compressed, or in proportion to the load which the spring is required to sustain; consequently the spring will be more or less strengthened by such increase of bearing.

Having described What I claim as ters Patent, is

The combination of the follower, or spring-bar A, carrying a concave-curved plate, a, and open guide D, the compound elliptic spring, formed of leaves, and the sill, or bolster B,with end-guides and supports, 9 g, substantially as described.

E. U. BENEDICT.

any invention, new, and desire to secure by Let- Witnesses W. A. DUNKLEE, GALVLN D. Wonn.

spring, in proportion as the lat- 

